The present invention relates to a control device for the selection of weft yarns in a knitting machine.
As it is known, there are knitting machines in which the control of weft yarns takes place by means of particularly complicated devices. A typical example can be found in the case of machines carrying a crochet-machine and a jacquard device on a single bearing frame.
The jacquard device controls the movement of the weft yarns and allows to obtain figured fabrics having very elaborated patterns. However, it requires the presence of selection and control members comprising hooked needles, a hooked needle trailing device, needles for the control of said hooked needles, as well as a selection drum that selects needles for the control of said hooked needles. In addition, said hooked needles act upon tie rods connected to rods that, by means of tubular weft yarn guides, control the feed of the weft yarn close to the needle-bar of a knitting machine.
Obviously such a unit is not only bulky and difficult to set up but it is expensive too and requires the constant employment of skilled operators.
It should be also noted that the selection drum for the needles controlling the hooked needles acts by way of a sheet or the like provided with holes for the possible introduction of the needles: so if even small faults are present the selection drum acts on the needles in an inexact manner.